login
Least natural number which does not occur in A116626(1..n).
5

%I #2 Mar 31 2012 13:21:11

%S 2,2,4,4,5,5,5,5,7,7,7,7,7,7,9,9,11,11,11,11,11,11,18,18,19,19,19,19,

%T 20,20,20,20,21,21,21,21,21,21,21,21,27,27,27,27,27,27,27,27,29,29,29,

%U 29,30,30,30,30,30,30,30,30,30,30,39,39,39,39,42,42,42,42,44,44,44,44

%N Least natural number which does not occur in A116626(1..n).

%o (MIT Scheme:) (define (A116648 n) (if (< n 2) (+ n 1) (let ((prev (A116648 (- n 1)))) (cond ((not (= (A116626 n) prev)) prev) (else (let loop ((i (+ 1 prev))) (cond ((> (A116627 i) n) i) (else (loop (+ 1 i))))))))))

%Y Cf. A116649, A116650, A116651.

%K nonn

%O 1,1

%A _Antti Karttunen_, Feb 21 2006